Can't believe that no-one has mentioned two big (well IMHO!) perks of the AA lounge - a help yourself sweetie bar (with takeaway bags helpfully provided), and - best of all - Portlebay popcorn! If there's a finer snack to be had, I haven't found it.
Since I rarely drink in lounges, and have a rather sweet tooth, I often opt for the AA lounge. Great service, decent wifi and although the ambience is a bit lacking compared with the competition, I love being able to leave with a bag of chocolates for the flight.